The BAD-PDW™, BAD-CSS™ and Ultra Compact Pistol SABERTUBE® using the patented VERT® buffer system have been tested on industry standard, factory Colt 6920 (direct impingement) to be a drop-in stock system using factory 5.56/.223 ammunition. However, due to the limitless possible configurations of the AR-15 rifle system from after market components and the variety of ammunition used, the rifle may be under gassed for the VERT® buffer system. Some adjustments or modification may be required.

The most common adjustment if the bolt fails to lock back on the last round is to open the barrel gas port diameter to increase the gas into the system to fully cycle and compress the inner buffer spring for reliable operation. An adjustable gas block, adjustable gas key or adjustable bolt carrier is recommended for tuning the gas system.

The VERT® buffer system have been tested successfully with 300BLK direct impingement AR platforms in semi-auto and full-auto fire. However, the rifle system must be configured properly. 300BLK supersonic and 300BLK subsonic ammunition have drastically different characteristics. They will also perform differently suppressed and unsuppressed. The rifle may be tuned to function on one end of the spectrum or the other. Please do not expect the stock to run on the same rifle configuration between shooting suppressed vs. unsuppressed and supersonic vs. subsonic.